Adjustable hydraulic trip release



2 Sheets-Sheet 2 Filed April 6. 1959 M Hm mm H N/k mfifl E mMA r L0 w A V0 um R N 0 4% NM W h Q \..NN\ .m v KN United States Patent Office 3,087,559 Patented Apr. 30, 1963 Placentia, Calif.

Filed Apr. 6, 1959, Ser. No. 804,210 13 Claims. (Cl. 175-297) This invention relates generally to well drilling equipment and relates more particularly to an adjustable hydraulic trip release for jars.

While the invention has particular utility in connection with oil well drilling equipment and the like, and is herein shown and described in connection therewith, it is to be understood that its utility is not confined thereto.

In the drilling of oil wells, the drilling string, or a portion thereof, may become jammed or stuck so that it cannot readily be pulled or raised. Under such circumstances a jar device may be connected to the upper end of the fish and used to jar the fish loose.

Various types of jars are known, some types being mechanical and other types being hydraulic in character. There are certain disadvantages to both types.

For example, some mechanical jars must be preset for a predetermined jarring force before lowered into the well. More particularly, should the device he set for 20 tons, only that force will be applied without raising the device to the surface and resetting it for a different jarring force. Such procedure takes considerable time and work which substantially increases the cost of drilling the well.

Other mechanical jars may be adjusted in the hole but considerable manipulation thereof is required to make such adjustments and the steps of such manipulation not only are time consuming but under some conditions, as where there is a crooked hole, may be very difiicult to carry out properly.

In hydraulic jars, changes in the oil viscosity greatly affects the operation of the device. As is well-known, the temperatures in wells varies considerably and should the device he used in a Well having a relatively high temperature, the oil in the jar is so thin that the device may fail to jar properly. Also, the device may fail for other reasons such as, for example, the bleed passage or passages becoming blocked or clogged. In such case, it also would be necessary to raise the jar to the surface and replace or repair same before fishing operations could be continued.

It is, therefore, an object of the present invention to provide a mechanism which will operate as a hydraulic jar or a mechanical jar.

It is another object of the present invention to provide a mechanism of this character having release means for converting the device from hydraulic actuation to mechanical operation.

It is still another object of the invention to provide apparatus of this character that may be embodied in various types of equipment, such as rotary jars, bumper safety joints, jar safety joints, and the like.

It is a still further object of the invention to provide apparatus of this character comprising a compact unit.

It is another object of the invention to provide a device of this character that is reliable and effective in operation.

It is still another object of the invention to provide a device of this character that is simple in construction and operation.

It is a further object of the invention to provide a device of this character that is relatively inexpensive to manufacture.

It is a still further object of the invention to provide a device of this character that is relatively easy to install, remove and/ or service.

The characteristics and advantages of the invention are further sufficiently referred to in connection with the following detailed description of the accompanying drawings which represent one embodiment. After considering this example, skilled persons will understand that variations may be made without departing from the principles disclosed, and we contemplate the employment of any structures, arrangements or modes of operation that are properly within the scope of the appended claims.

Referring to the drawings, which are for illustrative purposes only:

FIG. 1 is a side elevation of a jar device embodying the present invention;

FIG. 2 is an enlarged fragmentary view, partially in longitudinal section, showing the interior construction of the device;

FIG. 2A is a similar view of the upper end of the mechanism shown in FIG. 2;

FIG. 3 is a top plan view of the release mechanism per so with a portion broken away;

FIG. 4 is an enlarged longitudinal section of a portion of the hydraulic release shown in FIG. 2;

FIG. 5 is a sectional view taken on line 5-5 of FIG. 3;

FIG. 6 is an enlarged sectional view of one of the releasable lock means shown as positioned during the assembly of the device; and

FIG. 7 is a similar view showing same in the released position.

Referring more particularly to the drawings, there is shown a fishing tool embodying the present invention and said tool comprises a barrel unit, indicated generally at 10, and a mandrel, indicated generally at 12. The barrel unit comprises a tubular barrel 14 internally threaded at 15 for threadable reception of the lower externally threaded pin 16 of a top sub 17.

The mandrel 12 is of known construction and is provided with a passage there-through. There is a base 13 at the lower end having a depending, externally threaded pin 19 whereby the tool may be attached in the wellknown manner to a tool, pipe or the like. The mandrel includes a reduced diameter portion 20 above the base 18 which is slidably disposed within the lower end of the barrel 14, said barrel having an annular internal flange 22 just above the part 20 of the mandrel when the tool is in the fully telescoped position. The part 2% of the mandrel may be provided with slots for reception of keys on the interior of the barrel so that the device may be used as a safety release joint. This portion of the construction is known, being embodied in jar safety joints manufactured by the Shaffer Tool Works. Details of this portion of the tool are not shown as they do not enter into the present invention.

Extending axially upwardly of the portion 20 of the mandrel there is a second reduced diameter part 23 extending operably upwardly through the opening defined by the internal flange 22 of the barrel. The part 23 is provided at its upper end with an externally threaded portron, not shown, for threadable reception of the internally threaded lower end of a trip mandrel 25 which has substantially the same external diameter as the external diameter of the portion 23. The trip mandrel 25 is tubular and from the upper end thereof there extends a reduced diameter upper end portion 27 which may be secured to the trip mandrel in any suitable manner. For example, the two parts may be integral or they may be separate parts having a threaded connection or they may be welded or otherwise connected together.

Intermediate its ends the trip mandrel 25 is provided with a pair of longitudinally spaced eXternal annular grooves 28 which have diverging side walls, said grooves being of known character. Disposed on said trip mandrel 25, and adapted to have longitudinal movement relative thereto, is a trip spring, indicated generally at 30. This spring is of known character and includes an annular base 31 adapted to engage a shoulder 32 at the upper end of the internal flange 22, said shoulder being normal to the axis of the tool. Extending upwardly from the base 31 are a plurality of annularly spaced spring elements or fingers 34, each of said fingers having a pair of internal flanges 35 adjacent the free ends thereof, the sides of said flanges 35 corresponding to the annular inclination of the side walls of the grooves 28. The upper ends of said fingers 34 are also provided with external cam faces 36 which are inclined downwardly and outwardly relative to the axis of the trip mandrel. The external diameter of the spring is smaller than the inernal diameter of the adjacent portion of the barrel 14 and the lower end portions 37 of said fingers are of reduced thickness so that when said fingers are sprung outwardly at the upper ends, the primary spring action will occur at said end portions 37, there being sufficient space between the outer sides of said fingers and the inner surface of the adjacent portion of the barrel to permit sufficient outward movement of the upper ends of said fingers so that the flanges will move outwardly of the grooves 28 under conditions that will be described hereinafter.

Slidably disposed on the portion of the trip mandrel above the grooves 28 is a trip ring 40. The lower end 41 of said trip ring is provided with a cam surface 41 which is inclined downwardly and outwardly with respect to the axis of said ring and which abuts against the cam faces 36 of the fingers 34, the inclination of said cam surface corresponding to the inclination of the cam faces 36. The upper end of said trip ring extends above the upper end of the trip mandrel 25 and disposed on said upper end of the trip ring is a hydraulic trip control unit, indicated generally at 45.

The unit 45 comprises a tubular outer body 46 having oppositely extending annular flanges 47 and 48 at the upper and lower ends respectively of said outer body 46. At the upper end of the body 46 and extending inwardly of the flange 47 there is an upwardly facing shoulder 49. At the opposite end of the body 46 and extending inwardly of the flange 48 there is a downwardly facing shoulder 50.

The unit 45 also includes an inner body 52 which is provided at its lower end with an outwardly extending flange 53 of substantial length. The inner body 52 is disposed within the outer body 46 and is adapted to have relative longitudinal movement therewith. The flange 53 is provided with an external groove 54 for reception of a sealing element 55 which provides a seal with the inner surface of the flange 48. The sealing element 55 may be of any suitable character but is shown as an O-ring and has the necessary characteristics to resist the action of oil or other material with which it comes into contact.

Adjacent the upper end of the outer body 46, there is an internal annular recess 57 in which is disposed an O-ring 58 of suitable characteristics to provide a seal with the inner surface of the inner body 52.

The lower end 60 of the flange 53 rests on the upper end of the trip ring 40. The upper end of the flange 53 provides a shoulder 61 in spaced relation to the shoulder 50 of the outer body thereby providing an annular chamber 62 for spring means comprising a plurality of annular disc springs 63 of well-known character which react between the shoulders 61 and 50.

The upper end of the inner body 52 extends upwardly of the shoulder 49 of the outer body and said upper end of the inner body is spaced inwardly of the flange 47 of said outer body thereby providing a chamber 65 which is open at the upper end and in which is operably disposed a spring unit separator, indicated generally at 66. The lower end of the unit separator 66 is spaced upwardly somewhat from the shoulder 49, there being an inwardly extending flange 67 adjacent the upper end of said separator which overlies the upper end of the inner body but does not necessarily contact same. The unit also includes a flange 68 which extends longitudinally upwardly and has an outwardly projecting annular portion 69 which overlies the upper free end of the flange 47. Above the flange 67 and inwardly of the flange 68 there is an annular notch 70 at the upper inner part of said separator. The portion of the separator received in the space 65 is provided with an external annular groove 72 in which is disposed a sealing element or O-ring 73 to provide a seal between said separator and the inner surface of the flange 47. The separator is also provided with an internal annular groove 74 in which is disposed at similar seal 75 to provide an effective seal between said separator and the inner surface of the inner body. A fluid filling passage 66a is also provided in the separator 66 for filling the fluid chambers of the unit 45, said passage 66a being normally closed by a removable screw 66b.

The trip release unit 45 is provided with a connection between the shoulders 49 and 50. This connection is controlled by a check valve, indicated generally at 80. The check valve comprises an externally threaded body 81 threadably disposed in an internally threaded bore 82 which extends upwardly in the outer body from the shoulder 50 thereof. From the inner end of the bore 82 there extends a reduced diameter bore 83 which opens at its upper end at the shoulder 49. From the lower end of the check valve body 81 there extends a bore 84 which is internally threaded at 85 adjacent the lower end thereof. At the upper end of the bore 84 there is a wall 86 having a port 87 therethrough which connects the bore 84 with a bore 88 above said wall 86, said bore 88 communicating with the bore 82 and, hence, with the bore 83 in the outer body. Port 87 is controlled by a check valve which is disclosed as a ball 89 of smaller diameter than the bore 84 and said ball is urged into seating engagement at the lower end of the port 87 by a spring 90 which reacts between said ball and a plug 91 which is externally threaded and screwed into the lower internally threaded portion 85 of the bore 84. The plug 91 has a passage 92 therethrough providing a fluid connection between the chamber 62 and the bore 84 above said plug.

The outer body 46 of the unit 45 is provided with a bleed-off connection between the chamber 62 and the chamber 65, said bleed-off connection being shown in FIGS. 3 and 5. This connection includes a passage 95 in the outer body 46, said passage extending from the lower end thereof upwardly and at the lower end there is a counterbore 96 which is internally threaded for thread-able reception of a plug 97 which is provided with a calibrated orifice 98. The orifice 98 is of a predetermined capacity to provide the proper action for the device under predetermined conditions. Interchangeable plugs 97 with orifices of various effective sizes may be provided to meet various operating conditions and, of course, plugs having orifices of the same size may be provided for replacement should the plug be subjected to excessive wear such as would vary the effective size of the orifice therein and, hence, change the operation of the mechanism. It has been found that the orifice 98 should be extremely small. Under certain conditions which are encountered an orifice of .004" has been found to be highly effective. It is to be understood, of course, that the orifice size may be different under different operating conditions.

Above the unit 45 there is an annular chamber 100 between the reduced diameter portion 27 of the trip mandrel 25 and the inner wall of the barrel and within said chamber is disposed a plurality of annular disc springs 101. The upper spring 101 engages an annular adapter ring 102 seated against the lower end of the pin 16 of the top sub 17.

About the reduced diameter portion 27 of the mandrel 25 there is disposed a disc spring mandrel 103 having a somewhat greater inside diameter than the diameter of the part 27. The upper end of the mandrel 103 is provided with an out turned flange 104 in substantially the same plane as the adapter ring.

At the lower end the disc mandrel 103 is provided with a snap ring 105 received in a groove provided therefor in said mandrel and between said snap ring 105 and the lowest disc spring there is a snap ring spacer 106 against which the lowest spring 101 engages, said snap ring and spacer serve to hold the assembly of springs 101 on the disc mandrel. The part 69 of the separator ring 66 normally just touches the lower spring 101.

Secured in the top sub is a top sub sleeve 110 having an upper end portion externally threaded for threadable reception in an internally threaded part 111 of said top sub. The upper end of the tubular sleeve 110 has an internal diameter a little greater than the external diameter of the part 27 which extends into said sleeve. The lower end of said sleeve has an internally recessed part 112 in which is disposed packing 113. The upper end of the packing abuts against a shoulder 114 while the lower end is engaged by an adapter ring 115 held in position by a snap ring 116 disposed in an internal annular groove in the cylindrical wall defining the recess 112.

Means is provided for releasably locking the unit 45 in position in the barrel. Various means may be employed one of which is disclosed in FIGS. 2, 3, 6 and 7. There are a plurality of the locking means disposed in spaced relationship to each other about the periphery of the outer body 46 and as these devices are all of the same construction, a description of one will suffice.

There is a member 120 disposed in a semicircular recess 121 in the outer side of the body 46, said member 120 being rotatable on a pivot pin 122 which extends through said recess and terminates at its ends at the outer surface of the outer body 46. The member 120 has flattened sides 123 and 124 at opposite sides of the axis of said member, said sides 123 and 124 converging from an arcuate portion 125 to an arcuate portion 126 of smaller extent at the opposite side of the axis of said member. The portion 125 is provided with a peripherally extending arcuate groove 127 terminating in a shoulder 128. The groove 127 receives the free end of a leaf spring 129. The opposite end of spring 129 is received in a recess 130 provided therefor and said spring is secured therein by means of a screw 131. There is an internal recess in the wall of the barrel 14 for each of the locking members, said recess being arcuateiy formed at 133 at the upper end thereof and having a flat face 134.

which is inclined downwardly and inwardly from the lower end of the arcuate portion 133.

In installing the unit 45 the members 120 are disposed as shown in FIG. 6 with the side 123 facing the inner surface of the barrel 14. The unit 45 is slipped or moved longitudinally into the barrel until the members 120 reach the recesses 132 whereupon the springs 129 effect counterclockwise rotation of said members 120 so that the arcuate parts 125 thereof move into the recesses 132 and into engagement with the arcuate portions 133 thereof, the members 120 then being positioned as shown in FIG. 2. When members 120 are in this position, the unit 45 is securely locked in the proper location within the barrel 14. The members 120 are held in the locked position due to the fact that the faces 134 are closer to the central point for the curvature of the arcuate portions 133.

In order to insure proper operative movements between the barrel and mandrel, there is a floating separator ring disposed in an annular chamber 141 defined by the inner surface of the wall of the top sub 17 and the exterior surface of the top sub sleeve 110. The upper end of chamber 141 is vented at 142 to the exterior of the tool. This arrangement is well-known in the art and is part of certain of the jar tools manufactured by Shaffer Tool Works referred to above.

There is a tapped bore adjacent the lower end of the top sub 17, said bore being provided with a plug 146. This plug, and one of the usual safety shear pins, not shown, in the barrel of the device, are removed to fill the tool with suitable lubricating fluid of well-known character. One of the openings thus provided serves as a filling opening and the other as an air exhaust vent to insure proper filling of the tool. After the tool has been filled with the lubricating fluid, the plug 146 and the shear pin are replaced.

To operate the device as a jar after a fish has been engaged by tools below the present device, a straight upward pull is applied to the drill string which applies a corresponding pull to the barrel 14. The force of the upward pull will determine the force of the jarring blow provided by the present tool and must be at least the minimum for said tool. When the upward pull is applied to the string and barrel 14, upward pressure is applied to the tripping spring 30 through the shoulder of the flange 22. This pressure is also applied to the trip ring 49 and to the flange 53 0f the inner body 52. This force is, of course, resisted by the assembly of springs 101 above the control device 45 which exerts downward pressure on the spring unit separator 66 as soon as said separator 66 starts to move upwardly. The springs 101, under conditions hereinafter described, are adapted to provide the minimum jarring force for which the tool is designed. For example, if this tool has a range of 15 to 40 tons the springs 101 will be for 15 tons.

The pressure on the flange 53 applies pressure to the fluid in the chamber 62 which is forced upwardly through the passage 95 and orifice 98 into the chamber 65, the springs 63 simultaneously being compressed as well as the springs 101. As the chamber 62 is reduced in size with expulsion of the fluid into the chamber 65, the latter expands accordingly to accommodate the inflow of said fluid. After a predetermined transfer of fluid the trip ring will move upwardly and trip spring fingers 34 will be forced out of the grooves 28 so that the barrel will be lifted upwardly with a sudden movement and cause the knocker head, not shown, on the inside of the barrel to strike the knocker head, not shown, on the mandrel with a powerful blow.

The force of the blow of the jar device is determined by the lifting force applied to the string and barrel 14.

When the lifting force is relieved, the parts return to the position shown in FIG. 2, the fluid in the chamber 65 flowing back to the chamber 62 with relative rapidity due to the fact that it returns through the passage 83 which is relatively large and through the check valve 80 which has a relatively large port 87 and passage 92 for the flow of fluid therethrough. It is to be understood, of course, that when pressure is applied to the flange 53 to apply pressure to fluid in chamber 62 such fluid cannot flow through the check valve, only the return flow of fluid being permitted through this valve.

Should the hydraulic control unit 45 become inoperative from any cause such as, for example, plugging of the orifice 98 by foreign material, the tool may be converted into a spring controlled jar. This is effected by a pull upwardly on the string and barrel 14 with a predetermined force which is greater than the maximum for which the locking means of the hydraulic mechanism is designed. Such upward pull will cause the locking members 120 to be rotatively actuated so that they will assume the position shown in FIG. 7. Thereafter, the locking members are inoperative to hold the unit 45 in position for hydraulic control so that said unit will slide within the barrel. The device will then operate in the usual manner of jars, the force of the jar being then controlled by the springs 101 in the usual well-known manner and with the predetermined force said springs are designed to apply, which force is the minimum for the tool.

It is to be noted that the hole bore through the tool is full size.

It is also to be noted that while the construction and arrangement of the trip spring, trip ring and other parts of the device, with the exception of the unit 45, are of the character used in the jarring tools of the Shaffer Tool Works other types of trip mechanisms may be used and controlled by the hydraulic unit 45.

It is believed that the invention and many of its attendant advantages will be understood from the foregoing description and it is believed that it will be apparent that various changes may be made in the form, construction and arrangement of the parts of the invention without departing from the spirit and scope thereof or sacrificing all of its material advantages, the arrangement hereinbefore described being merely by way of example.

We claim:

1. A jar trip release mechanism, comprising: a tubular mandrel unit including a part for attachment to a part below same and an upwardly extending part, a tubular part mandrel removably attached to said upwardly extending part and coaxial therewith and including an upwardly extending reduced diameter part, said trip mandrel having a pair of external annular grooves therein; a barrel unit including a tubular barrel telescopically receiving the upper portion of the mandrel unit and having an internal annular flange defining an opening for reception of the upper portion of the mandrel unit which is movable longitudinally in said opening, said flange defining an upwardly facing shoulder; a top sub secured to the upper end of the barrel; a tubular trip spring operably disposed on the mandrel unit, said trip spring having an annular base resting on the shoulder in the barrel and including a plurality of upwardly extending spring fingers each having a pair of internal ridges adapted to be received in the external grooves of the trip mandrel, there being a cam face at the upper end of each ridge; a trip ring on the trip mandrel, said ring having an annular cam surface at the lower end engageable with the cam surfaces of the said fingers; a tubular hyraulic trip release means above said trip ring, said trip release means including a tubular outer body having longitudinally extending annular flanges at each end, said body having a bleed passage extending from the lower end to the upper end and including a calibrated bleed oriflce and a second passage extending from the upper to the lower ends, a check valve operably disposed for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage; an inner tubular body having an outwardly extending annular flange at the lower end seated on the upper end of said trip ring, said inner tubular body being operably disposed within the outer tubular body with the flange of the inner tubular body slidably related to the depending flange of the outer body and defining, with the lower end of said outer body, a reservoir for fluid; an annular spring unit separator slidably disposed above the outer body and between the upwardly extending flange thereof and the upper end portion of the inner body, said unit separator having parts overlying the upper ends of said upwardly extending flange of the outer body and the upper end of the inner body with the lower end of said separator spaced from the upper end of the outer body to thereby define with said outer body a fluid chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; sealing means between the inner and the outer bodies and the unit separator; spring means in said reservoir urging relative movement of the inner and outer bodies to increase the size of said reservoir; means carried by said outer body for releasably securing said trip release means in said reservoir in a predetermined position in the barrel and releasable by a predetermined force exerted on the barrel in an upwardly direction; a spring assembly comprising a plurality of annular disc springs disposed between the reduced diameter part of the trip mandrel and the inner surface of the barrel and engageable with the lower end of the top sub; means at the lower end of said spring assembly limiting expansion thereof, the lower spring normally just engaging a portion of said spring unit separator; and sealing means providing a seal between the reduced diameter portion of the trip mandrel and an adjacent portion of the barrel unit which is sildable on said reduced diameter portion of said trip mandrel.

2. A jar trip release mechanism, comprising: a tubular mandrel unit including a part of attachment to a part below same and an upwardly extending part, a tubular trip mandrel removably attached to said upwardly extending part and coaxial therewith and including an upwardly extending reduced diameter part, said trip mandrel having a pair of external annular grooves therein; a barrel unit including a tubular barrel telescopically receiving the upper portion of the mandrel unit and having an internal annular flange defining an opening for reception of the upper portion of the mandrel unit which is movable longitudinally in said opening, said flange defining an upwardly forcing shoulder; a top sub secured to the upper end of the barrel; a tubular trip spring operably disposed on the mandrel unit, said trip spring having an annular base resting on the shoulder in the barrel and including a plurality of upwardly extending spring fingers each having a pair of internal ridges adapted to be received in the external grooves of the trip mandrel, there being a cam face at the upper end of each ridge; a trip ring on the trip mandrel, said ring having an annular cam surface at the lower end engageable with the cam surfaces of the said fingers; a tubular hydraulic trip release means above said trip ring, said trip release means including a tubular outer body having a longitudinally extending annular flange at each end, said body having a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice and a second passage extending from the upper to the lower ends; a check valve operably disposed for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage; an inner tubular body having an outwardly extending annular flange at the lower end seated on the upper end of said trip ring, said inner tubular body being operably disposed within the outer tubular body with the flange of the inner tubular body slidably related to the depending flange of the outer body and defining, with the lower end of said outer body, a reservoir for fluid; an annular spring unit separator slidably disposed above the outer body and between the upwardly extending flange thereof and the upper end portion of the inner body, said unit separator having parts overlying the upper ends of said upwardly extending flange of the outer body and the upper end of the inner body with the lower end of said separator spaced from the upper end of the outer body to thereby define with said outer body a fluid chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; spring means urging relative movement of said bodies to increase the capacity of said reservoir; means carried by said outer body for releasably securing said trip release means in a predetermined position in the barrel and relesable by a predetermined force exerted on the barrel in an upwardly direction; a spring assembly comprising a plurality of annular disc springs disposed between the reduced diameter part of the trip mandrel and the inner surface of the barrel and engageable with the lower end of the top sub; and means at the lower end of said springs limiting expansion thereof, the lower spring normally just engaging a portion of said spring unit separator.

3. A jar trip release mechanism, comprising: a mandrel unit, a tubular trip mandrel attached to said upwardly extending part and coaxial therewith and including an upwardly extending reduced diameter part, said trip mandrel having a pair of annular external grooves therein; a barrel unit including a tubular barrel telescopically receiving the upper portion of the mandrel unit and having an internal annular flange defining an opening for reception of the upper portion of the mandrel unit which is movable longitudinally in said opening, said flange defining an upwardly facing shoulder; a top sub secured to the upper end of the barrel; a tubular trip spring on the mandrel unit and resting on the shoulder in the barrel and including a plurality of upwardly extending spring fingers each having a pair of internal ridges adapted to be received in the external grooves of the trip mandrel, there being a cam face at the upper end of each ridge; a trip ring on the trip mandrel and having an annular cam surface engageable with the cam surfaces of the said fingers; a tubular hydraulic trip release control unit above said trip ring, said unit including a tubular outer body, having a depending flange, said body having a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice and a second passage extending from the upper to the lower ends of said body; a check valve operably disposed for controlling said sec ond passage to permit flow of fluid downwardly but preventing reverse flow through said second passage; an inner tubular body having an outwardly extending annular flange at the lower end which rests on said trip ring, said inner tubular body being operably disposed within the outer tubular body with the flange of the inner tubular body slidably related to the depending flange of the outer body and defining, with the lower end of said outer body, a reservoir for fluid; an annular unit separator slidably disposed above the outer body and having parts overlying parts of the outer body and the inner body with the lower end of said separator spaced from the upper end of the outer body to thereby define with said outer body a fluid chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; and spring means urging relative movement of said bodies to increase the capacity of said reservoir; means carried by said outer body for releasably securing said control unit in a predetermined position in the barrel and releasable by a predetermined force exerted on the barrel in an upwardly direction; a plurality of annular disc springs disposed between the reduced diameter part of the trip mandrel and the inner surface of the barrel and engageable with the lower end of the top sub; and means at the lower end of said springs limiting expansion thereof.

4. A jar trip release mechanism, comprising: a tubular mandrel unit and a tubular trip mandrel coaxially attached thereto; a barrel unit including a tubular barrel telescopically receiving the upper portion of the mandrel unit; a top sub secured to the upper end of the barrel; a tubular trip spring on the mandrel unit and operably connected to the barrel so as to be raised upwardly thereby and including a plurality of spring fingers each having means releasably engaging the trip mandrel, said fingers also having a cam face at the respective upper ends thereof; a trip ring on the trip mandrel, said ring having an annular cam surface at the lower end engageable with the cam surfaces of the said fingers; a tubular hydraulic trip release means above said trip ring, said trip release means including outer and inner bodies movable longitudinally relative to each other, one of which is provided with a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice and a second passage extending from the upper to the lower ends of said one body; a check valve operably disposed for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage, parts of said bodies defining a fluid reservoir, variable in size with movements of said bodies relative to each other; an annular unit separator operably disposed relative to said bodies and defining therewith a variable fluid chamber, said passages interconnecting said reservoir and chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; means carried by said outer body for releasably securing said trip release means in a predetermined position in the barrel and releasable upon a predetermined force being exerted on the barrel in an upwardly direction; a plurality of annular disc springs disposed between the reduced diameter part of the trip mandrel and the inner surface of the barrel and engageable with the lower end of the top sub; and means at the lower end of said springs limiting expansion thereof, the lower spring normally just engaging a portion of said spring unit separator.

5. In a jar mechanism: a tubular mandrel unit including a tubular trip mandrel attached thereto; a barrel unit including a tubular barrel telescopically receiving the up per portion of the mandrel unit, a top sub secured to the upper end of the barrel; a tubular trip spring on the mandrel unit and operably connected to the barrel so as to be raised upwardly thereby and including a plurality of spring fingers each having means releasably engaging the trip mandrel, said fingers also having a cam face at the respective upper ends thereof; a trip ring on the tripmandrel, said ring having an annular cam surface at the lower end engageable with the cam surfaces of the said fingers; a tubular hydraulic trip release device above said trip ring, said device including outer and inner bodies longitudinally movable relative to each other, one of which is provided with a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice and a second passage extending from the upper to the lower ends, a check valve operably disposed for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage, parts of said bodies cooperating to define a fluid reservoir of variable size; means urging relative movement of said bodies for increasing the size of said reservoir; an annular unit separator operably disposed relative to said bodies and defining therewith a variable fluid chamber, said passages interconnecting said reservoir and chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; means carried by said outer body for releasably securing said trip release device in a predetermined position in the barrel and releasable by a predetermined force exerted on the barrel in an upwardly direction; spring means disposed between the reduced diameter part of the trip mandrel and the inner surface of the barrel and cngageable with the lower end of the top sub; and means at the lower end of said springs limiting expansion thereof.

6. In a jar mechanism: a tubular mandrel unit; a barrel unit telescopically receiving the upper portion of the mandrel unit; a trip spring operably interconnecting the barrel and mandrel units so as to be moved longitudinally by relative movement of said units in one direction and a plurality of spring fingers each having means releasably engaging the trip spring, said fingers also having a cam face at the respective upper ends thereof; a trip ring on the trip mandrel, said ring having an annular cam surface at the lower end engageable with the cam surfaces of the said fingers; hydraulic trip release means above said trip ring, said trip release means including outer and inner bodies longitudinally movable relative to each other, one of said bodies being provided with a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice and a second passage extending from the upper to the lower ends of said one body, a check valve operably disposed for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage, parts of said bodies cooperating to define a fluid reservoir of variable size; an annular unit separator operably disposed relative to said bodies and defining therewith a variable fluid chamber, said passages interconnecting said reservoir and chamber, there being liquid filling said reservoir, chamber and the passages in the outer body; means carried by one of said bodies for releasably securing said trip release means in a predetermined position in the barrel and releasable by a predetermined force exerted on the barrel in an upwardly direction; spring 11 means disposed within said barrel unit and having a predetermined loading, said spring being rendered operable for jarring when the trip release means is released from the barrel unit.

7. In a jar mechanism, comprising: a tubular mandrel unit; a barrel unit telescopically receiving the upper portion of the mandrel unit; a trip spring operably interconnecting the barrel unit and mandrel unit interlocking said units but releasable when a predetermined upward force is applied to the barrel unit; a trip ring on the mandrel engageable with said trip spring; hydraulic trip release means engageable by said trip ring, said unit including parts having movement relative to each other and defining variable fluid chambers interconnected by a calibrated bleed passage through which fluid is forced when force is applied to the barrel unit; and a return passage between said chambers; a check valve operably disposed for controlling said return passage to permit flow of fluid but preventing reverse flow therethrough; means carried by said trip release means for releasably securing said means in a predetermined position in the barrel unit and releasable when a predetermined force is exerted on the barrel in an upwardly direction; and preloaded spring means adiacent said trip release means for providing sudden release of the barrel unit.

8. In a jar mechanism: a tubular mandrel unit; a tubular barrel unit, said mandrel unit and barrel unit being telescopically arranged and adapted to have relative longitudinal movement; trip release means normally locking the units against relative movement, said trip release means tripping when a predetermined force is exerted on the barrel unit thereby unlocking said trip release means so as to permit relative longitudinal movement between said units for jarring and resetting; a trip ring on the mandrel unit having one end engaged by said trip release means; hydraulic trip release control means disposed between said units and having movable parts defining chambers for fluid therein with a calibrated bleed passage between said chambers and a return passage, one of said parts engaging the other end of said trip spring; a check valve controlling the return passage to permit return flow but to prevent flow in the opposite direction through said return passage, the parts of the hydraulic control being operably arranged so that fluid will be forced from one chamber to the other through the bleed orifice when there is a longitudinal pull on one of said units; releasable latching means carried by one of the parts of said hydraulic trip release control means securing said trip release in a predetermined position in said barrel unit; and spring means disposed between said units, said spring means having a predetermined loading and having one end engageable with the hydraulic trip release control means, said spring means being preset for a minimum jar and rendered operative upon release of the releasable latching means for said hydraulic control means.

9. In a jar mechanism: a tubular mandrel unit; a tubular barrel unit, said mandrel unit and barrel unit being telescopically arranged and operable to have relative longitudinal movement; trip release means normally locking the units against relative movement, said trip release means being adapted to trip under a predetermined force exerted on the barrel unit thereby unlocking so as to permit relative longitudinal movement between said units for jarring and resetting; a trip ring on the mandrel unit having one end engaged by said trip release means; hydraulic trip release control means disposed in one of said units and having movable parts defining chambers for fluid therein, there being a calibrated bleed passage between said chambers for flow of fluid from one chamber to the other, and a check valve controlled return passage, one of said parts operably engaging the other end of said trip ring; releasable latching means carried by one of the parts of said bydraulic trip release control means securing said trip release control means in a predetermined position in said barrel unit; and yielding means disposed in one of said units, said yielding means having a predetermined loading for eflecting jarring action and rendered operative upon release of the releasable latching means for said hydraulic trip release control means.

10. A tubular hydraulic trip release control means for use in a jarring tool including a barrel unit, comprising: a tubular outer body having longitudinally extending l annular flanges at each end, said body having a bleed passage extending from the lower end to the upper end and including a calibrated bleed orifice, and a second passage extending from the upper to the lower ends of said outer tubular body; a check valve operably disposed 15 for controlling said second passage to permit flow of fluid downwardly but preventing reverse flow through said second passage; an inner tubular body having an outwardly extending annular flange at the lower end, said inner tubular body being operably disposed within 90 the outer tubular body with the flange of the inner tubular body slidably related to the depending flange of the outer body and defining, with the lower end of said outer body, a reservoir for fluid; an annular unit separator slidably disposed above the outer body and between the upwardly extending flange thereof and the upper end portions of the inner body, said unit separator having parts overlying the upper ends of said upwardly extending flange of the outer body and the upper end of the inner body with the lower end of said separator spaced from the upper end of the outer body to thereby provide a fluid chamber, said chamber and reservoir being connected together by said bleed passage and said second passage, there being liquid filling said reservoir, chamber and said bleed and second passages in the outer body; sealing means between the inner and outer bodies and the unit separator; spring means urging relative movement of the inner and outer bodies to increase the size of said reservoir; means carried by said outer body for releasably securing said trip release control means in a predetermined position in the barrel unit of said tool and releasable by a predetermined force exerted on the barrel in an upwardly direction.

11. In a tubular hydraulic trip release control means adapted to be installed in a jarring tool having a barrel unit: a tubular outer body having longitudially extending annular flanges at each end; an inner tubular body having a radially outwardly extending annular flange at the lower end, said inner tubular body being operably disposed within the outer tubular body within the flange of the inner tubular body slidably related to the depending flange of the outer body and defining with the lower end of said outer body, a reservoir for fluid; an annular unit separator slidably disposed above the outer body and between the upwardly extending flange thereof and the upper end portion of the inner body, said unit separator having parts overlying the upper ends of said upwardly extending flange of the outer body and the upper end of the inner body with the lower end of said separator spaced from the upper end of the outer body to thereby provide a fluid 6O chamber, there being a calibrated bleed connection between said reservoir and said chamber and a return passage therebetween; a check valve operably disposed for controlling said return passage to permit flow of fluid to the reservoir but preventing reverse flow through said return passage; yielding means urging relative movement of the inner and outer bodies to increase the size of said reservoir; means carried by said outer body for releasably securing said trip release control means in the barrel unit and releasable by a predetermined force exerted on the barrel unit in an upwardly direction.

12. In a jar mechanism: a mandrel unit; a barrel unit telescopically arranged relative to the mandrel unit; mechanical trip release means embodied in said mechanism and releasably interconnecting the units together, said units being normally locked by said mechanical trip release mean-s against relative movement; a trip ring on the mandrel unit having one end engaged by said trip release means; hydraulic trip release control means within said barrel unit for effecting release of the trip release means in accordance with the force of the longitudinal pull in one direction on the barrel unit, the other end of said trip ring operably engaging said hydraulic trip release control means; normally inoperative spring means operably disposed in said barrel unit between said mechanical trip release means and said hydraulic trip release control means; and means securing said hydraulic trip release control means in a predetermined position in said barrel and releasable when a force is applied to said barrel unit in excess of a predetermined value.

13. In a jar mechanism: a mandrel unit; a barrel unit telescopically arranged relative to the mandrel unit; mechanical trip release means embodied in said mechanism, including releasable locking means for releasably interconnecting the units together, said units being normally locked against relative movement by said releasable locking means; a trip ring on the mandrel having one end engaged by said mechanical trip release means; hydraulic trip release control means within said barrel unit; securing means for positively but releasably connecting said hydraulic trip release control means against movement relatve to said barrel, said hydraulic trip release control means, when thus secured, effecting release of the trip release means in accordance with the predetermined force of a longitudinal pull in one direction on said barrel unit, the other end of said trip ring being engaged by said hydraulic trip release control means; spring means reacting on one end of said hydraulic trip release control means; said jar mechanism, when the hydraulic trip release control means is secured against movement in the barrel, functioning as a hydraulically controlled jar and said jar mechanism, when said hydraulic trip release control means is released from connection to said barrel unit, functioning as a spring controlled jar mechanism, said spring then controlling the force of said jar, said securing means being actuated to release said hydraulic trip release control means from positive connection with the barrel unit upon a predetermined upward pull on the barrel unit.

References Cited in the file of this patent UNITED STATES PATENTS 1,401,111 Sigel Dec. 20, 1921 1,804,700 Maxwell May 12, 1931 2,008,743 Black July 23, 1935 2,126,241 Black Aug. 9, 1938 2,144,869 Boulter Jan. 24, 1939 2,309,872 Shaller et a1 Feb. 2, 1943 2,621,024 Koppl et a1 Dec. 9, 1952 

12. IN A JAR MECHANISM: A MANDREL UNIT; A BARREL UNIT TELESCOPICALLY ARRANGED RELATIVE TO THE MANDREL UNIT; MECHANICAL TRIP RELEASE MEANS EMBODIED IN SAID MECHANISM AND RELEASABLY INTERCONNECTING THE UNITS TOGETHER, SAID UNITS BEING NORMALLY LOCKED BY SAID MECHANICAL TRIP RELEASE MEANS AGAINST RELATIVE MOVEMENT; A TRIP RING ON THE MANDREL UNIT HAVING ONE END ENGAGED BY SAID TRIP RELEASE MEANS; HYDRAULIC TRIP RELEASE CONTROL MEANS WITHIN SAID BARREL UNIT FOR EFFECTING RELEASE OF THE TRIP RELEASE MEANS IN ACCORDANCE WITH THE FORCE OF THE LONGITUDINAL PULL IN ONE DIRECTION ON THE BARREL UNIT, THE OTHER END OF SAID TRIP RING OPERABLY ENGAGING SAID HYDRAULIC TRIP RELEASE CONTROL MEANS; NORMALLY INOPERATIVE SPRING MEANS OPERABLY DISPOSED IN SAID BARREL UNIT BETWEEN SAID MECHANICAL TRIP RELEASE MEANS AND SAID HYDRAULIC TRIP RELEASE CONTROL MEANS; AND MEANS SECURING SAID HYDRAULIC TRIP RELEASE CONTROL MEANS IN A PREDETERMINED POSITION IN SAID BARREL AND RELEASABLE WHEN A FORCE IS APPLIED TO SAID BARREL UNIT IN EXCESS OF A PREDETERMINED VALUE. 